Explosively actuated tool with magnetic head

ABSTRACT

An explosively actuated tool for driving a stud into a metal object includes a collar secured to the front end of a sleeve containing the barrel of the tool. Disposed around the collar is a plurality of magnets that are rigidly connected to it. The magnets project forward for engagement with a metal object in order to hold the front end of the tool against it during firing of the tool.

United States Patent Giebel et al. [451 Sept. 26, 1972 EXPLOSIVELY ACTUATED TOOL 3,565,312 2/1971 Temple et al ..227/9 WITH MAGNETIC HEAD FOREIGN PATENTS OR APPLICATIONS [72] Inventors: Joseph L. Giebel, Pittsburgh; Ernest Tempk, Murrysvine, both of p 729,824 5/1955 Great Britain ..227/ I I 944,708 6 1956 G ..227 ll [73] Assignee: Mine Safety Appliances Company, ermany 1 l v PmSburgh Primary Examiner-Granville Y. Custer, Jr. [22] Filed: Nov, 13, 1970 Attorney-Brown, Murray, Flick & Peckham [21'] Appl. No.: 89,198 [57] ABSTRACT I e An explosively actuated tool for driving a stud into a metal Object includes a collar Secured to the from end [58] 'l 9 T l of a sleeve containing the barrel of the tool. Disposed I o earc around the collar is a plurality of magnets that are rigidly connected to it. The magnets project forward [56] References Cited for engagement with a metal object in order to hold UNlTED STATES PATENTS the front end of the tool against it during firing of the t I. 1,365,870 1/1921 Temple 227/9 00 3,354,658 1 1/1967 Leonardi ..227/9 X 4 Claims, 5 Drawing Figures 26 3/ L5 3 32 28 30 /z 2 7 the? i' a 20 v I T1 1 A} a 9 /a 5 7 "mu i /0' /9 /5 /7 /6 6 EXPLOSIVELY ACTUATED TOOL WITH MAGNETIC HEAD Some explosively operated tools are, used under water. One use for which they are adapted is for driving studs into the metal hull of a ship or into an escape hatch cover of a submarine. It is necessary to hold the front end or head of the tool securely in place during the firing operation so that the tool will not shift its position laterally or separate from the object that it is placed against until after. the stud has been driven along a line as perpendicular to the object as possible. Holding the tool in place by handis very difficult, so other means have been provided for holding the tool but they require the handling of additional items or considerable manipulation of the tool to fasten it in driving position temporarily.

Preferably, these are cylindrical magnets 25 pressed into circumferentially spaced sockets 26 in a ring 27 that encircles the front end of the collar. The sockets open forward and the magnets project from their front ends. The rear end of the ring seats against a radial shoulder 28 extending around the collar, and the ring is held in place by set screws 29 threaded in radial It is amongthe objects of this invention to provide a tool for driving a stud into a metal object which can be quickly and easilyapplied to and removed from the object, which will be held in proper position'during the driving operation, and which does not require, separate means for attaching the tool to the object.

The invention is illustrated in the accompanying drawings, in which FIG. 1 is a side view of a tool,.partly in section, attached to a metal object;

FIG. 2 is a front end view of the tool;

FIG. 3 is a side view as the tool is being removed from the object;

FIG. 4 is a side view of a'modiflcation; and

FIG. 5 is a front view of the modified tool.

Referring to FIGS. 1, 2 and 3 of the drawings, a metal object, such as a submarines convex hatch cover 1, into which a stud is to be driven, is shown with an explosively actuated tool in position to drive the stud. The tool includes a metal sleeve 2, on the rear end of which a flanged ring 3 is screwed. Screwed onto the front end of the sleeve is a circular collar 4 that extends ahead of it, and slidably mounted in this collar is a cap 5 that has a central hole 6 in its front end. The cap is screwed onto a barrel 7 that extends back through the sleeve and out through the flanged ring, in which it can slide. The front end of the collar is provided with a circular recess 8 having a threaded side wall, in which a retaining washer 9 is screwed. The opening in this washer is smaller at its rear end than the hole through the cup to form an annular shoulder 10. The cap 5 normally is held against the washer by a friction ring 11 seated in an annular groove in the encircling collar. A recoil shock absorber in the form of a coil of tubing 12 may encircle the barrel and extend from the flanged ring 3 to cap 5.

Screwed onto the projecting rear end of the barrel is a breech block 14 that engages a plug 15 closing the rear end of a hollow piston 16 in which there is a charge of explosive powder 17. "Removably attached to the front end of the piston is a stud 18 that is to be driven into the hatch cover when the powder is ignited by a spring-pressed firing pin 19 slidably mounted in a tube 20 extending rearwardly from the breech block.

It is a feature of this invention that this tool can be quickly, easily and securely attached to the hatch cover by simply placing the head of the tool against the cover. Accordingly, several permanent magnets are carried by the collar in positions to engage the hatch cover so as to magnetically attach the front end of the tool to it.

openings through the ring between the magnets. The inner ends of the screws project into a peripheral groove 30 in the collar. The ring may be provided with a hole 31 through the back wall of each socket 26, so

.that the magnets can be driven out if they require In'using this tool the head of it is simply placed I against the hatch cover in the position shown and the magnets will hold it securely in-place. The firing pin then is released, which causes a primerto explode the powder and drive the piston and stud forward through the barrel. The .stud will pass partway through the retaining washer-and penetrate the hatch cover. The head of the stud will engage washer shoulder 10 to limit the distance the stud can pass through the washer. Dur ing this operation the barrel will recoil in the sleeve and separate the piston from the stud. The recoil shock will be absorbed by the crushing of the tubular shock absorber as the barrel moves rearwardly in the sleeve.

Since the retaining washer now is joined to the hatch cover by means of the stud, the tool must be disconnected from the washer in order to remove the tool from the hatch cover. This is done by means of a spanner wrench which can project into a radial hole 32 in the collar behind'the magnet ring to unscrew the collar from the washer. The unscrewing also serves to back the magnets away from the hatch cover so that the tool is free fromthe cover by the time it separates from the retaining washer. I

In the modification shown in FIGS. 4 and 5, the tool is the same except for the collar and the magnets. In this embodiment, the collar 35 is a square block that is screwed onto the front end of the sleeve 36, and the magnets are horseshoe magnets 37. Each side of the block is provided with a curved recess 38 that is open at its front end. A horseshoe magnet fits in each recess with its pole pieces projecting beyond the front of the block. The magnets are attached to the block by means of screws 39 extending through them and screwed into the block. The side walls of the recesses prevent the magnets from rotating on the screws. The front ends of the pole pieces are beveled so that they will conform to the curved surface of the hatch cover, to which the tool is applied. This tool is operated in the same manner as the one first described. After it has fired a stud into a hatch cover the collar is rotated to unscrew it from its retaining washer 40.

Since the magnets are a part of the tool, it is unnecessary to handle separate elements for holding the tool in operative position. It is simply placed .in the desired location, where it stays until removed by the operator.

According to the provisions of the patent statutes, we have explained the principle of our invention and have illustrated and described what we now consider to represent its best embodiment. However, we desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwisethan as specifically illustrated and described.

We claim:

1. A tool for driving a stud into a metal object, comprising a sleeve, a barrel slidably mounted in the sleeve for recoil therein, means for holding a stud in the rear portion of the barrel, a collar secured to the front end of the sleeve, a plurality of magnets disposed around the collar, means rigidly connecting the magnets with the collar, the magnets projecting forward for engagement with a metal object to hold the front end of the tool against it, and means connected with the rear end of the barrel for firing an explosive charge to drive the stud forward into the metal object, said collar being provided with a central circular recess having a threaded side wall for receiving a threaded washer that can be screwed into it, the washer being adapted to be secured to said object by said stud, whereupon the tool can be unscrewed from the washer.

2. A tool as defined in claim 1, in which said magnetconnecting means include a ring encircling the collar and provided with a plurality of circumferentially spaced sockets having open front ends, the ring having threaded radial openings therethrough between said sockets, and set screws disposed in said openings and bearing against said collar to hold the ring thereon, said magnets being rigidly mounted in said sockets and projecting from their front ends.

3. A tool as defined in claim 1, in which said collar is a square block, the magnets are horseshoe magnets engaging the sides of the block and projecting forward therefrom, and said magnet-connecting means are screws extending through the magnets and into the sides of said block.

4. A tool as defined in claim 3, in which each side of said block is provided with a recess that is open at its front end, and each magnet fits in one of the recesses and is positioned thereby. 

1. A tool for driving a stud into a metal object, comprising a sleeve, a barrel slidably mounted in the sleeve for recoil therein, means for holding a stud in the rear portion of the barrel, a collar secured to the front end of the sleeve, a plurality of magnets disposed around the collar, means rigidly connecting the magnets with the collar, the magnets projecting forward for engagement with a metal object to hold the front end of the tool against it, and means connected with the rear end of the barrel for firing an explosive charge to drive the stud forward into the metal object, said collar being provided with a central circular recess having a threaded side wall for receiving a threaded washer that can be screwed into it, the washer being adapted to be secured to said object by said stud, whereupon the tool can be unscrewed from the washer.
 2. A tool as defined in claim 1, in which said magnet-connecting means include a ring encircling the collar and provided with a plurality of circumferentially spaced sockets having open front ends, the ring having threaded radial openings therethrough between said sockets, and set screws disposed in said openings and bearing against said collar to hold the ring thereon, said magnets being rigidly mounted in said sockets and projecting from their front ends.
 3. A tool as defined in claim 1, in which said collar is a square block, the magnets are horseshoe magnets engaging the sides of the block and projecting forward therefrom, and said magnet-connecting means are screws extending through the magnets and into the sides of said block.
 4. A tool as defined in claim 3, in which each side of said block is provided with a recess that is open at its front end, and each magnet fits in one of the recesses and is positioned thereby. 